The present invention relates to high density arrangement of elements in a single package, and more particularly relates to high density arrangement of a modular Input/Output (I/O) package in a data processing system.
Packaging inefficiency in the area of I/O has previously been identified by others, and an attempt has been made to create an improved structure. However, the resulting efforts have only moderately improved density and in many cases have resulted in the application of unique I/O cards as opposed to the use of standard PCI adapter cards.
U.S. Pat. No. 5,672,509 issued Jun. 9, 1987 to Speraw for AIR COOLING ASSEMBLY IN AN ELECTRONIC SYSTEM ENCLOSURE discloses an air cooling assembly in a system enclosure for cooling a plurality of logic module cassettes located in the system enclosure.
U.S. Pat. No. 5,317,477 issued May 31, 1994 to Gillett for HIGH DENSITY INTERCONNECTION ASSEMBLY discloses a high density computer interconnection assembly in which a plurality of flat packages are slidably mounted along a rack in a frame, an interconnection circuit board at right angles and connected to components in the flat packages, and memory cards coupled to the opposite side of the circuit board.
U.S. Pat. No. 6,025,989 issued Feb. 15, 2000 to Ayd et al. for MODULAR NODE ASSEMBLY FOR RACK MOUNT MULTIPROCESSOR COMPUTER discloses a modular node assembly wherein a removable chassis having disk drives, power supply, and a fan is removably mounted in a logic chassis having processor cards, I/O cards and memory cards.
U.S. Pat. No. 6,137,684 issued Oct. 24, 2000 to Ayd et al. for CAMMING MECHANISM FOR JOINING MODULAR ELECTRONIC ENCLOSURES discloses a camming and latching mechanism for locking a removable chassis having disk drives, power supply, and a fan into a logic chassis having processor cards, I/O cards and memory cards.
I/O and storage devices are key components in any server. The overhead required to employ these devices in a server greatly affects the resulting physical size, cost and availability of a server. The present invention has enabled a single enclosure of I/O and storage hardware to replace what has been approximately three enclosures of a similar physical size in previous product offerings, with the single enclosure having improved fault tolerance over the multiple enclosure approach. The single enclosure approach reduces cost and component count appreciably.
A unique packaging and subsystem structure has been invented that makes it possible to contain, power, cool and maintain concurrently (hot plug) a large amount of high performance I/O and storage hardware in a very compact space in a low cost fashion with a clean and neat physical appearance. This structure has components arranged so that all parts in the enclosure can be serviced without sliding out or removing the enclosure from the system. The I/O and storage hardware contained within the structure includes:
20 full length/full power Peripheral Component Interconnect (PCI) cards;
2 high bandwidth I/O planars each with a dual host connection;
4 imbedded Small Computer System Interface (SCSI) controllers (2 contained on each I/O planer);
16 one inch high speed SCSI hard drives; and
4 Hard Drive Backplanes.
It is an object of the present invention to use a modular puzzle like structure that packages components within fault containment regions in a hierarchical fashion that enables concurrently maintaining the most failure prone components without disturbing any other component in the unit, and then maintaining a second level of less failure prone fault containment regions without affecting other such regions in the unit.
It is a further object of the present invention to use cassettes to house PCI cards enabling simple insertion and extraction of I/O adapters.
It is a further object of the present invention to use the physical positioning of the 2nd level fault containment regions with respect to one another to enable the use of only two centric power supplies and four air moving devices to power and cool all I/O and storage hardware in the enclosure with complete power and cooling hardware fault tolerance (redundancy). The use of high speed instantaneous current limiting hardware on the 2nd level and 1st level fault containment regions is also an employed technique that enables this.
It is a further object of the present invention to use service controllers packaged internal to the two redundant power supplies so that the service control function is fully redundant, fault tolerant and concurrently maintainable. This technique enables the higher density achieved by eliminating service controls on each 2nd level fault containment region. The use of redundant service controllers improves availability considerably, and assures that a controller is always available to light the amber LED""s (Light Emitting Diodes) that are carefully placed throughout the unit to identify components that require replacement.
It is a further object of the present invention to use the association of elements with respect to one another to enable proper airflow over the components without a significant amount of dedicated space for air flow management. Adequate air flow is maintained over all components even in the case of an air moving device failure or temporary removal of a faulty element that must be replaced. Air is pulled through the power supply units and disk drives by the air moving devices and is exhausted across the components on the planar board through the PCI adapter cards.
It is a further object of the present invention to use simple air moving devices that physically contain only a simple motor and wheel, and rely on brushless/sensorless drive electronics contained within the power supplies. This technique enables the air moving devices to be buried within the unit, behind 2nd level fault containment regions due to the very low air moving device failure rate that this technique yields.
It is a further object of the present invention to package all of the I/O and storage components and the supporting power and cooling hardware with a minimum number of wire type cables, thereby providing a clean and neat appearance and aiding ease of service. All of the units in the drawer blind plug through the use of autodocking connectors easing service operations.
It is a further object of the present invention to use a completely passive compact mid-plane structure in the center of the enclosure to interconnect the 2nd level fault containment regions. The completely passive nature of this element provides the required level of availability for this element, since it represents the only potential single point of failure in the subsystem.
It is a further object of the present invention to use a 4 EIA high overall enclosure that mounts in a standard 24xe2x80x3 EIA rack, thereby providing system level packaging flexibility.
It is a further object of the present invention to use an enclosure level power and service control interface that consists of 4 identical compact cables, which plug directly into the front of the power supplies. These interfaces provide cross redundant connections to the entire subsystem very cost effectively, with the capability of concurrently servicing any of the cables. Each of the interface cables contain 350 VDC power and a full duplex differential RS-422 control interface.
It is another object of the present invention to provide a component arrangement that enables servicing all parts in the enclosure without sliding the unit out or removing it from the system.
It is another object of the present invention to provide a component arrangement that enables a full compliment of fault identification LED""s (1-2 per serviceable unit), with all of the LED""s being physically packaged on the components of the unit as opposed to on a dedicated unit for LED""s, and with all of the LED""s being visible from the front and rear of the enclosure with the enclosure fully installed in the system.
It is another object of the present invention to provide an air moving device with a unique latching and retention mechanism that enables it to be concurrently maintained after removing a DASD backplane assembly.